which are the best spread betting sites?

Why not try browsing the www.sportsspread.com? I heard it's a well-known betting company.

Check www.gamebookers.com too.This site is one of my favorite.

I think the best bet is to find one that others can recommend and then compare the lines they give you, to see the most consistent spreads. I use Pointspread.com for seeing where every site has there lines for every event, it's easy to see and it is setup right there for you, also has all the books for u to choose with the links.