If you do your embroidery using a machine and want to find some exciting and new designs to get down to work, you’ll be very happy to learn about this site, which sells a variety of mostly complex and advanced patterns for machine embroidery, though I wasn’t able to learn in what styles and methods; similar sites offer things like Freestanding Lace and Photo Stitch, but there’s no mention to things of that sort here. Since in order to download the patterns users have to become members of the site (and pay a fee), probably the best way to check out if you feel comfortable with these formats and patterns is to give a try to the free downloadable designs, where you can see if the required level of ability suits you; as per the machines, a list of models and makes with available patterns is on the homepage, so that’s a good way to start your search as well.
If you are happy with what you got in the trials, you’re probably best advised to go on to purchase the designs of your preference through the site, as the nicer and more interesting patterns are obviously not free; the site’s collection is very ample in terms of themes, and you will be able to find everything from alphabets to religious motifs, and from fine art designs to holiday themes. I was quite happy to see that there’s lots of information and support on computer and design programs, as the patterns are digital, and well, not everybody is a complete computer ace (nor has to be: the site is about embroidering!). ArtisticThreadWorks.com also hosts a forum where users join to discuss their hobby and meet people interested in similar activities. 
