For startup hubs such as San Francisco, New York etc, I think the best job boards are https://jobs.github.com/, http://careers.stackoverflow.com/jobs/, http://www.authenticjobs.com/, and https://angel.co/jobs
Angellist as mentioned on another comment is also great for just finding startups.
I also used to find really good city specific sites with a google search like "startups [CITY NAME]" or even "startup jobs [CITY NAME]"
for berlin for example one of the first hits is: http://berlinstartupjobs.com/
Also, there is a huuuge list with job boards, currated by the guys from underdog.io -> https://docs.google.com/spreadsheet/pub?key=0AlOCi7qqICWzdEh...
if you are interested in remote jobs, and dont want to wade through all those job boards yourself, subscribe to http://remoteworknewsletter.com and set a couple of filters to only receive jobs that are relevant to you
Search the news archives for startups in the local business journal corresponding to the market where you're interested in living/working.
Go back to 2009-13, put together a hit-list of promising targets, see where they are today. In Dallas> http://www.bizjournals.com/dallas/print-edition/2013/09/20/n...
*Pro-Tip: Reach out to the CEO directly, not all jobs are posted.
Beyond that, feel free to e-mail me (my address is in my profile, slightly obfuscated)...I'm founding a startup that's aimed at people like you, and I'd love to get your feedback on a new product concept.
would love your thoughts. email in profile.