get a cheap web host. 5 bucks a month will do the trick. then you can practice php or .net or perl or anything else to your hearts content. i reccomend learning .Net (especially C#) AND php. Once you can get around a bit, start picking up T-SQL. If you are using PHP check out MySQL. If you are using .Net try to find a host with MS SQL Server.
Database programming is typically the most valuable skill a web programmer can have, but you need to become adept with a programming language or 2 first.
Web design is nice, but is of little value compared to database programming and it pays a lot lower. Of course it all boils down to what you enjoy the most. Become an expert at a few things a be familiar with as many as possible.
From Monster, median salaries for the SF Bay area:
Web Designer III (4+ years experience): $80,684
Senior Java Developer (4-6 years experience): $105,318
Data Architect (4-6 years) $95,686
Senior Software Engineer: $98,743