Like everyone else says, being sociable, and letting people know you're there, but be warned, spamming other people's journals and shout pages with links is a good way to annoy people. The most effective thing I've found so far is the banner ads.
However, once you have people's attention, you have to have something to show them, and I'm going to have to say this, you're not there yet. There's a lot of competition out there, and if you're entertaining notions of offering price over quality, however low you think you can go, somebody will undercut you. You have to be better.
You need to work on your basics, and post more, but I would say instead of focusing on requests, show people what you can do. What do you like to draw, and most importantly, what do you like doing that nobody else is doing? If you can get a rep as the go-to guy for something that can work in your favour. You do have some pretty generic looking characters in your gallery, and you need art that sticks in people's brains. Word of mouth is important to getting watchers so the more people going, "Hey did you see what Kasz did?" the better. Technical skill is certainly important, but people like to feel things too. Erotica is the traditional path, but it's certainly not the only one. People also like it if you can make them laugh, feel sad, or just oo and ahhh at something they've never seen before. This is also the toughest part, just because it is so nebulous. You can make a piece of art that you think has all the right things, but it can still be greeted with a shrug.
The most important thing to remember is that none of this is going to release a flood of commissions. It takes a while to build up a following, and the more satisfied customers you have, the more who will recommend you to others. The more watches and faves you have, the more people who will be showing off your work to others. You have to be patient.
