Thanks again for the replies, this is a lot of help to me.

Grasschopper, I priced out a 10spd setup and it came to over $400 for shimano 105 parts, if I went with a few tiagra parts it could bring the price down a little... its just not worth it given my budget for the one extra gear.

I saw those prices Dtrain, its a great deal for the 105 levers, hard to pass that one up.

So it sounds like all I would need is a new chain, shifters and cassette?