I've been wondering where I can find nema tags because I have fixtures that could use a tag but I can't find any.

Any help would be greatly appreciated.

I go to one of those custom vinyl sticker places for mine. I'm not sure if the files for NEMA tags are online but you can make them in a program like Inkscape and have that printed on a square 3"x3" label which is the same size as "real" NEMA tags. If you want to see the end result, all of the MV streetlights in my collection have these homemade NEMA tags.

They're supposed to be waterproof but I'm not sure how long they last before fading outdoors.

If you want the real tags, you can order them in packs of 25 from the following places:
Electromark
Tek I.D.

There are probably more places that sell these. Try searching for "luminaire wattage label" or "NEMA luminaire wattage label" online.

Thanks for this, as I need just a couple of 5's and 40's. The tekid.com site lists weird mixed-up colors: green for MV, blue for M-H, red or yellow for HPS, but the red background can be used for low pressure sodium.

Is there a market for such labels if I buy a bunch of them as required per min purchase? I'd try and list the extras on ebay for sure.