I've got this welder that I've used for all my body work so far... and since I can't afford gas for it all my welding has been done with flux-core wire...
http://www.sears.com/shc/s/p_10153_12605_00920569000P?prdNo=2&blockNo=2&blockType=G2
I use the method that Irishman999 mentioned to weld...