Salary negotiation is one of the worst and most dreaded things you'll have to deal with when you look for a job and it's hard as a someone starting out in the professional world to figure out how to deal with it and how much to ask for. These days, many companies will even ask you on the application what your salary expectations are, so it's increasingly hard to take the common advice of avoiding the question all together of deterring it by saying something like "it's negotiable." So, how do you figure out what salary to ask for?
Cost of Living
Start by figuring out the cost of living in the area where you are looking to work. How much does an apartment cost, how much are groceries, gas, etc.? A lot of this information can be found online. One of the best ways to do this though is to figure it out while you are actually interning.
If you can, do an internship in the city you're hoping to work in and keep track of how much you spend each month while you are there including rent, food, cell phone, living expenses, and fun stuff. Of course, you'll be on a tight budget as an intern, but that won't change much in an entry level position. What you spend interning over a summer can be very helpful when it comes to figuring out how much you need to be able to survive in that city. Of course, your costs will probably be higher in the "real world" because you'll probably have wonderful things like students loans to worry about and taxes to pay that weren't a part of the equation as an unpaid intern, so make sure you account for that. Then, use this information to project your costs for a year as a starting point to figuring out what kind of salary will be acceptable.
The next step is to figure out what a reasonable salary range is for the type of position you're looking for. There are plenty of web sites that will help you get information about salaries for a specific job title within a specific city including Salary and GlassDoor. Still, the best way is actually to talk to friends, professors, and mentors in your field to find out specifically what you can expect. You may even be able to talk to a career advisor at your college to find out salary averages for graduated from your major. Ask friends who work for the company if they know what the job you applied for is budgeted at, look at job descriptions that match your experience, Google, and make notes when salary does occasionally come up in an interview. Use this information to construct a range and figure out if it matches the salary needs you determined in Step 1. Salaries tend to be lower in the music industry than their non-music counter parts, so you may find that your needs don't actually match with your dream job. In that case, you may need to consider getting a weekend job to supplement your income, eating into any savings you might have, starting work in a different city with a lower cost of living, or even getting a better paying job to gain more experience and save until you can afford something lower.
Set It and Forget It
Remember that line from some late-night infomercial product? It was probably related to some cooking product, but it applies here too. If you've done the research, determined your cost of living, talked to your mentors and professors to determine a reasonable salary range, and you know that there are in fact jobs out there doing what you want and paying what you want, then stop worrying about it and realize that you are worth it. It's easy to fret that if you ask for too much you won't get the job, or that if you ask for too little you will sell yourself short, but if you have the experience, aren't letting your ego get the best of you, and have research to back your decision, then you have reason to feel confident in presenting your salary range. In that case, it may be the company's loss. This isn't about entitlement or pretension, it's actually more like self respect. It's about not doing 90 hours of work for 20k when you know for a fact you could find a similar job for 40k, or not listing 30k as your required salary on your application just to get the job when you know your experience and skills are worth at least twice that (that is why the research is so important first). Sure, it is harder is a tough economy and you may need to be willing to take a pay cut simply to try to make ends meet, but that doesn't mean you have to be willing to settle for something outlandish. The laws of supply and demand say that if you're not willing to pay the asking price for a great product, you'll have to settle for an inferior substitute. So, if you know you're great at what you do, and have established a reasonable salary range based on plenty of research and recommendations, then don't waste your time worrying about the companies that are missing out.