Several posters here have the right idea. Finish your class first unless you are POSITIVE this is going to be something you are going to keep with. Its not uncommon for me to sell complete packages to people who are either in or getting ready to start their class. This is not the norm though.
When you are ready to purchase your first regulator, don't "cheap out". This is not to say you have to spend a ton of cash for a good regulator, but do a bit of research and purchase the best piece of equipment you can afford, as it is something you will probably use for a good long time. When budgeting for your reg, remember you also need guages/computer, an octo and if you don't own a bcd, you'll need to purchase a BCD inflator hose as well.
The good thing is every manufacturer makes a good regulator in your price range. Removing people's opinions on "who is best", think about what you liked or didn't like about the gear you've used. No adjustments, or don't care if it does? Venturi switch? Or don't care. Swivel on the hose or don't care? Once you have an idea of what features you like then start looking around at where you can get the best deal on that particular item.