There is an amazing number of fabrics being produced. I find Fabric Shack is an excellent website to use, to keep up with what's coming out, as they carry a wide variety and their website is a breeze to use. If you click on 'shop', and then on 'new arrivals' (or however it is they phrase that), and do this a few times a week or month, you can quickly make note of what's recently come out. If you go to Hawthorne Threads (specializing in modern fabrics) and sign up for their newsletter, which is beautifully set up and easy to scan through, and if you go to Shabby Fabrics and sign up for their newsletter, which is equally beautiful and easy to scan through, you will pretty much have the new fabric lines covered.
As for choosing -- that's a different story! My main goal is to try and resist buying fat quarter bundles, which use up such a big chunk of the monthly budget. But I find them so appealing.