heaps of top info in here bro
http://www.dubstepforum.com/viewtopic.php?t=14797
have been getting some good sounds using various bass specific VSTi's, but the main key im finding is layering, my current effort has 3 layers for each individual bass line, all at varying volume levels, with each layer having specific freq ranges, within the freq range that i want to keep the bass i.e, if my lead bass is sitting between 100 - 250, then ill have one 100 - 150, one at 150 - 200 etc all cut using hi/low pass filters . I find this gives a really full wholesome sound. Also my sub bass is completely independently masterd from the other basses, but with the same note patterns.
In saying thqat, im no expert, there a peeps who know a million times more than i.