I'm getting my tongue pierced and I know there is numbing spray I just don't know if I can buy it

Why not just use oragel? It's meant for oral use, so you know it's safe for ingestion and shouldn't irritate the piercing.

You should talk to your piercer before using it, though.

Eating ice cream can help keep the pain and swelling down afterward.

No there is nothing that will numb your tongue enough for a piercing not to hurt.

Most numbing creams and sprays need to stay on the area for up to 2 hours... I doubt you could hold your tongue out for that long for it to be effective, and even then they only numb to a certain depth, that's why they are used for tattoos.