OP, make damn sure you do your homework on which audio interfaces work well with your operating system. I'll repeat it again:
MAKE SURE YOUR USB INTERFACE WORKS WITH YOUR OS!!!
plenty of manufacturers will claim that their boxes work with both Microsoft OS's and Mac's, but in reality they're buggy pieces of donkey feces that will crash your computer every 15 minutes. Focusrite for example, tends to be fine with Apple stuff but will rarely if ever work on windows. MOTU gear is highly dependent upon which particular box you're using: some of the older ones only run on Mac, but I've been having great results with the new AVB model on Windows 8.
Do your homework, look up reviews on each box you're interested in, and check the product support forums for complaint threads.
As far as other gear like dedicated DI boxes goes, I'm gonna go against the grain here and suggest that you hold off on getting one just yet. It's very possible to get a great sound by just plugging straight into the USB interface and playing with the raw audio files. It will force you to experiment with EQ and compression plugins, which in turn will help you understand what they do, how they work, and how to make anything sound good. Outboard gear can wait until a few years down the line when you need that extra little bit of polish. It will be useless to you if you don't yet know the fundamentals of mixing and how to make everything jive together.
Good luck, have fun, and when you start to hit a wall (which you will), just keep on experimenting and reading until all the little pieces start to click into place. Once you get past the frustration of "Everything sounds like crap and nothing works", and start figuring out a few little things at a time, you'll be surprised by how quick you start thinking "wow, everything is sounding pretty good now".
MAKE SURE YOUR USB INTERFACE WORKS WITH YOUR OS!!!
plenty of manufacturers will claim that their boxes work with both Microsoft OS's and Mac's, but in reality they're buggy pieces of donkey feces that will crash your computer every 15 minutes. Focusrite for example, tends to be fine with Apple stuff but will rarely if ever work on windows. MOTU gear is highly dependent upon which particular box you're using: some of the older ones only run on Mac, but I've been having great results with the new AVB model on Windows 8.
Do your homework, look up reviews on each box you're interested in, and check the product support forums for complaint threads.
As far as other gear like dedicated DI boxes goes, I'm gonna go against the grain here and suggest that you hold off on getting one just yet. It's very possible to get a great sound by just plugging straight into the USB interface and playing with the raw audio files. It will force you to experiment with EQ and compression plugins, which in turn will help you understand what they do, how they work, and how to make anything sound good. Outboard gear can wait until a few years down the line when you need that extra little bit of polish. It will be useless to you if you don't yet know the fundamentals of mixing and how to make everything jive together.
Good luck, have fun, and when you start to hit a wall (which you will), just keep on experimenting and reading until all the little pieces start to click into place. Once you get past the frustration of "Everything sounds like crap and nothing works", and start figuring out a few little things at a time, you'll be surprised by how quick you start thinking "wow, everything is sounding pretty good now".