I am wondering what size of bank roll that I should be playing with in low-limit poker online? I want to know what limit I should start at with the discretionary money that I have

Well I am going to answer with the type of answer many people hear and don't listen too. Anyway I think that if you follow what Chris Ferguson has written about for ever is a great way to start and then make it your own as you play and learn more about your playing tendencies. If you don't know what his bankroll management is you can always get it from fulltilt pros list. The jist of it says that you should have at least 10 buy ins to a ring game and 20-30 buy ins for a s-n-g and 20-50 buy ins for a mttl. So I hope this help you in your start. This is a very difficult to follow but it works well. So let me know how it is going.