I just discovered Unity Stamps friends with Flair and won my first time. Also crop chocolate has weekly challenges. I need to get more scrapping ones done because I need to catch up my scrapping and I have a ton of cards at the momment
Check out Practical Scrappers for a Card Contest that will run through February. First round is due tomorrow but it can be something you've already uploaded. It is love or valentine theme. Top 25 go on for the next round etc. til winner. Prizes are great!