When you're flexible as far as where you would travel to work and the type of work you're willing to do, CoolWork.com's Help Wanted Now listings include jobs that employers are seeking to fill right away.
CoolWorks.com also has a variety of other summer job listings ranging from entry level jobs to positions for seasonal professionals.
Another way to find immediate openings is to search the job search engines by keyword. For example, if you use "immediate" or "immediate start date" or "immediate opening" as a keyword you'll find job posts for employers seeking help now. Be sure to include your location, so the list of jobs includes the location where you want to work.
Here's more advice on finding companies that are hiring now.
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