What are useful websites for scouting GIS related jobs?
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GIS Jobs Clearinghouse is a great site for both posting and finding Geospatial related jobs. I have used it to fill my last three vacancies. You don't need to create an account to search the jobs which is a big bonus. They even have an option to display job postings via a map as well as a twitter account announcing new postings.
This isn't GIS specific, but dice.com is a pretty good resource for the US. Especially if you are looking for something a little more technical (not just map production, but something that uses analysis or programming skills). When I would receive calls for a job that I hadn't directly applied for, I would ask where they found my resume and Dice had the most hits.
From my experience when I was job hunting last year, many of the jobs on GIS Clearinghouse and GIS Jobs were out of date.
I've found indeed.com to be pretty good, I always find the greatest number of postings there. They seem to be the Google of job searches, with jobs from many obscure sites coming up in the results. You can narrow the search by state and can sort by greatest relevance or newest postings.