Hey! I downloaded them from a Pokemon fan site (Bulbapedia I think), then made a composite image with them in GIMP (a free program similar to photoshop), uploaded it to Imgur, and embedded it in my signature from there. I can't actually remember why I made a composite image now - you can have multiple images in your signature, so I could have just uploaded all the sprites to Imgur individually.
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Puddle
Ace Trainer D
Oooh I see. Thanks. The ones I have are from Bulbapedia archive but they are up to Gen V only 
Puddle
Check out the list of Pokemon by National Pokedex number, all the up-to-date menu sprites are there. If you left-click on them it just goes to the Pokemon's article, but if you right-click on them and select "view image" or "save image" you should be able to download them.
The Pokemon Database has a really good sprite archive as well, and it seems that they don't mind people hotlinking directly from their site, but I haven't been able to get the embed codes to work. Using the regular image URL works, but I'm not sure whether they mind people doing this or not. You could still download them and re-upload them somewhere else.
If you left-click on them it just goes to the Pokemon's article, but if you right-click on them and select "view image" or "save image" you should be able to download them.The Pokemon Database has a really good sprite archive as well, and it seems that they don't mind people hotlinking directly from their site, but I haven't been able to get the embed codes to work. Using the regular image URL works, but I'm not sure whether they mind people doing this or not. You could still download them and re-upload them somewhere else.