How do they do this?

So I've been reading a little bit about linkbuilding and came across these guys:

forumlinkbuilding . com/view/link_building_service?framepr9-11024
thebacklinkbuilders . com/index2.html?gclid=CIqqgtrwkKMCFdFN5Qodd3UQoQ
forumlinkbuilding . com/view/link_building_packages

How do they manage to come up with so many related sites and keep up with the huge link building? Can I achieve the same thing using scrapebox? (just bought a copy for my own site, but want to be sure)

TIA

You need good footprints (ie. queries that you put into google to find related forums) Once you have a good footprint then you can use it in an automated tool like scrapebox which can also sort by PR.

As google limits your results and doesn't allow you to see everything indexed for a search query then you have to creative to get more out of google by doing things like asking for only the .net or .org results in your query or some other modifiers to make your query unique and to get more results.

Hope that helps a bit.