Will they build the entire PC? If so anyone know a roundabout price.

I don't believe so. Smaller shops are more likely to do that sort of thing.

I'd back up Bill. They have an insane selection of PC parts and very few prebuilt PCs. If you want to build your own PC asking one of the techs will help you out with any questions you have regardless compatibility and performance. As for the actual assembly, I don't believe they do that. You'd have to put it together yourself.

If you mean custom built, I believe they do. Price would depend on what you wanted. I'd say, for a decent system, 1K