For inexpensive liquid, a lot of folks seem to like StrictlyEjuice... it's dekang though - but I have enjoyed it... Madvapes has topvapor... dekang, but good stuff... Some of the Happysmokes signature liquids are inexpensive and USA made... some folks love the good prophets stuff... not too expensive...
Scan the classifieds... scan the suppliers forum for deals. Freedomsmokesusa just did 120mls for 30.00. Backwoods brew just did 25% off...
Most of the stuff I buy is $14.00-23 per 30ml... seems worth it... If I were on a tighter budget, I suppose I would look at one of the vendors I mentioned above.