[pjungwir]

For your local area, I'd look at who is sponsoring the tech events (e.g. you local Ruby/JS/iOS/etc meetup). For instance in Portland that quickly gets me New Relic, Urban Airship, and maybe a dozen other names. You can also see if there is a local tech magazine/newsletter, and read a few issues. If you're looking for younger companies, look at the class list of the last few years of local accelerator programs.

If you're looking for remote work, you could start with the list of YC companies. Or just go with any young companies whose products or blog posts or people you admire.

It's better to start with the companies you want to work for, and check their own jobs pages (or ask someone who works there), than to start with aggregated job boards, which are really a wasteland.