It sounds like you have a better idea of what they're selling for right now than I do. Check ebay recent sales for some ideas. I figure at some point the price will have to go down, these comics just aren't very rare. it was a huge hit when it came out and there are thousands out there. It's only from the 80's lots of people have taken very good care of these comics since they were first published. I have one or two copies of each issue from when they came out, all pretty sweet looking. Probably not 9.8s, but if I have them so do a lot of other people.
If you want to sell them, go for it. It sounds like you've got these comics to make money, now's a good time for Watchmen.
As for getting them graded, there's only one way. Send them off to CGC. You could also send them to PGX, but CGC has a better rep and will likely bring more cash.
what do I got? see for yourself: http://www.comicspriceguide.com/world/default.asp?m=Speedy-D
Thanks to Kree_boy411 I've discovered the Comic Book Realm