I needed consistantly sized logos for one of my recent projects. While Google Image Search is really quite good, I still had a lot of trouble finding images that were:
I ended having to do a fair bit of work to get them looking okay, and figured others might benefit as well.
I am not the copyright/trademark/etc owner of any of these. Use them at your own risk.
If you are the owner and do not want your logo here, please let me know (nicely) and I will be glad to remove it. No lawyers necessary: just submit an issue on github! Just so you know: I am usually using them on a credits page (example), so it might be in your best interests to let me slide. Alternatively, it would be great if you provided the appropriately sized images yourself.
I am definitely not an artist, and generally do not do anything besides resize and rearrange existing artwork.