There's a few places I get my images for Teespring from.
If they're simple, I'll do a search within Teespring images itself. If they're a little more complex however, I might find free images in Google.
Most of the time, I just use dollarphotoclub.
You can get some awesome, ready to upload images just for $1.
Over time, you'll accumulate a data base of images you can tweak here and there to suit your niches and you'll find yourself not spending much on images.
The below tutorial goes through their database, I highly recommend using them, in most cases it'll end up cheaper than hiring a designer.
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