Here's where I order my tags from,
they will sell blank or with your website/address/phone/etc printed free on the opposite side. I get the 1/2" x 5" Printed Tags for $39.50 per 1000. They come on a roll so just peel off what you need. I use a Brother label maker from Target to put the individual plant names on the blank side. The tape for this label maker is very good and doesn't come off/fade like Sharpie markers do.
If you want small pots and trays do yourself a favor and buy them from the same people, trays and pots made by different companies are not always interchangeable which is very frustrating! Novosel that Mark Ca suggested is a good place. You can also find pots and matching trays on ebay. I like square because you can fit more in a compact space.
I like square for that reason too. It saves space.
I have a brother printer! I like it, but the tape is so expensive! I use it for all my neps though.
thank you all for these websites, that is really helpful. I appreciate it! I got really worried when my local store stopped carrying the small pots and the tags that I was using. I use a lot of tags, but not so many pots. I basically just use the small pots for my succulents. I use 4 inch or bigger for my carnivorous plants.