Q: How do I purchase an album at the store and have it sent via email to my son.

If you have a credit card on your account (you can't use an acocunt's balance for gifting), and his iTunes account is in the same country as yourself (you can't gift to other countries), then you should be able to gift it from within the store to him : http://support.apple.com/kb/HT2736 - that should send an email to the email account that you enter on the gifting screen, which he can then redeem onto his account.