I agree with Owl..sounds like a Min Pin!
Anyhow...you really just need to work with him and hopefully he will get use to it.
You can try a dremel, but some dogs just hate to have their feet even touched, so that may not work.
The only option I can think of is to walk him alot on the concrete. I know you said he is afraid of everything, but he is just going to have to get use to it. It's going to take time and alot of patience and work on your part, but he has to get over things. Is your driveway blacktopped? Walk him around on that.
Do you know how to cut nails? Are his nails white so you are able to see the kwik easily? The only other thing I can think of is for you to try. I had a Rottie that hated her nails done. Took 3 of us to hold her down and I still couldnt get them done. So I would do the sneak attack on her....when she was sleeping, I would sneak up with the nail trimmers and do one nail at a time. I had to be quick about it though and I only got one shot at it. Just do not trim back so far that you make him bleed. I would keep a muzzle and some kwik stop on hand just in case.
I dont know about the tranq's...Im not a big fan of them myself. I have seen some dogs go the other way on tranq's and have seen some owners give too much that the dog is out for hours and hours. I personally would only use it as a last resort...thats just me though.