If you get "free" designs, make sure they are from a reputable site like Embroidery Library. Many free designs are not digitized well, and you will waste your time and materials. We've all learned the hard way on that score. Janome, Pfaff, Viking, Bernina, Babylock, Brother, have free designs on their websites. My favorite is also Emb Library; their prices are very reasonable and very worth it and they run specials etc. Get on their monthly email list, I just got mine this morning, and can't resist buying at least one design. The other good thing about EmbLibrary is once you buy your design (in your format) they keep it on their site for you in case you lose yours and need to re-load it.
There are hundreds of excellent designs and design sites. It can become an addiction... ask me how I know ! I was/am addicted to monograms, that's a whole other discussion.
Have fun !