What types of customers have you worked with?
I do a lot of hard drive data recovery. Most people don't realize the importance of backing up their irreplaceable photos, videos, and music files until they lose all of it. Depending on the damage done, I can usually re-construct some or all of the lost files using industry-best software tools and forensic techniques.
I also do a lot of virus removal, system clean-up and optimization, and general hardware troubleshooting.
On the web side of things, I've been working mostly with local musicians to put together the site features they need in an affordable way.
What advice would you give a customer looking to hire a provider in your area of work?
For computer services, find someone trustworthy. A lot of shops have some high school student working in the back room for a low hourly wage, who doesn't have any inhibitions about snooping through your files and making his own copies of anything interesting. I've also heard a lot of stories involving providers who didn't do a thorough job, or who (probably intentionally) broke something else in the process.