Selling old gear, need opinions on value.

Another source is KEH.com, a reputable store which buys and sells used equipment, and also sells some items new. Offer your cameras, lenses, adapters and flash to them on their site and see how much they will pay. If you agree to the prices, just sell to them, if you don't, you can assume that you will get a bit more, with more effort, selling everything yourself. Keep in mind that, after they give you an initial estimate based on your description of the condition of your equipment, they will inspect and may give you a different amount. I've always found them honest and fair.

On your other question: Since you are planning to move to digital, and will be buying what you need for it, it will cost less to learn with digital, because you can get much more practice shooting without paying for film and processing. Thirty rolls of film with processing will cost you approximately the same as purchasing a used D90.

Keep the Canon gear and become proficient on its use. That will help you when you switch over to digital. You can always sell it later.

If you sell these items, sell them individually, not as a package. You'll get much more money for them that way. Your better venue might be Ebay. At least you don't have to waste dealing with (as many) flakey people. If you advertise on CL, don't use the email response, as you will get spammed/scammed. Use a phone number instead (very expensive call from Nigeria). Don't deal with anyone who claims to be out of the country or who wants to handle any sort of payment through Western Union. Only cash and carry in a mutually agreed public place (e.g. a Wendy's).

I agree with Sarah about eBay.

But I think your expected price is way too high. The non-lens accessories are worth almost nothing, as are the third party lenses.

(I've bought an Ftb and ME Super on eBay.)

I've bought about 100 classic cameras on eBay. I would not pay even half of $400 for this assemblage.

Which is not to say that the bodies aren't great. Only that a zillion of them were made, and so well made that many, many of them are still around.

I'd keep 'em. Both the Canon Ftb and Pentax are great shooters. The FTb is a tank and the Pentax is super compact. You're a bit optimistic on your lens prices. They have more value as working tools than cash value.

I just gave away a whole slew old filters, flashes, and other accessories, not even bothering to try to sell them since I knew they had no market value.

The only FD bodies that fetch much money these days are the F-1's, and perhaps the EF and T90. As for FD lenses, people only really want (and are therefore willing to pay for) the faster ones. And third party manual focus lenses, apart from a very few such as the Kiron and Vivitar Series 1 macros, are unfortunately worth nothing.

This makes no sense to me. You have some beautiful lenses listed here and nice cameras.
The FD lenses are among some of the best quality glass ever made. Unless you already have Nikon lenses. In that case it is the move, but as a new system if you need to raise money for it , your already handicapping yourself by starting into an expensive brand system. You would do sooo much better to purchase a mirror-less camera like the Sony Next or one of the the Panasonic Lumix G cameras or Olympus Pen's. You can then buy cheep adapters to use all the lenses you have and along with the kit lens that comes with it you would be set. You can do all this for less than what you would pay for that Nikon you are thinking of, and have more lenses and a very good system. Also having the film bodies available if you wanted to shoot some B&W film or find an occasion where you just wanted more shallow depth of field for certain shots, by shooting a roll of film and having it scanned, you would need a full frame digital camera or very expensive fast lenses to achieve the same result and it might not be financially possible or easy for you.
When I wanted to get a Digital SLR to use for the photography degree I was getting, people kept suggesting i sell all my camera gear and get a Nikon or Canon DSLR , but i have many fine old lenses and even if i sold them all i would not be able to buy much more than an SLR with its Kit lens. SO i did my research and ended up buying a used Panasonic G1 for a few hundred dollars and kept all my old gear, and boy am I Glad i did. My professors and most professionals suggest we shoot and focus manually anyway so it would have been a waste of money to upgrade to auto-focus lenses unless i did sports Photography. All totaled i spent less then 500 on my camera kit (including a wide angle native lens i needed to get, 14mm prime) and flash and have more quality focal lengths and faster lenses than most other students in my classes except those that spent over a thousand on their kits, which there are only 2 of. So if you are really trying to save money. Save it , and don't sell your good inexpensive lenses. Just buy a body that it works on. You will be glad you did trust me. Unless you do have to worry much about money to spend on a camera system, in which case go ahead as you planned and buy into one of the most expensive brand system out there.

So are you convinced yet to just keep it and use it?
Also i forgot to mention you might think about saving up and buying a Pentax DSLR. I don't know how many lenses you have for it but all older Pentax lenses work on the heir DSLR camera. How many Pentax mount lenses do you have?

As others have said, I think your prices on the lenses are high. I usually only pay $20-$25 for a 50mm lens unless it is very fast. When I bought my Canon FTb, it was $15 and came with a 50mm ƒ1.4 lens. I won't tell you what I paid for my Pentax ME Super with a 50mm ƒ2.0, it wasn't even half of what you are asking. I use them both regularly. As far as film goes, I shoot a lot of black and white and I buy it in 100 foot lengths when I can and it is less that $70, sometimes less that $35. A 100 foot roll will provide 20 36 exposure rolls, process it yourself with about $20 in chemistry. Sure the equipment to do that will be a bit but once you have it, it pays for itself quickly. Besides, its magic when you pull a roll of your own negatives out of the wash and hang them up to dry. Not very hard at all.
Before you dump them you might give them a try, who knows, you may even like it.