Learn Russian: Это мой адрес.

In Russian, the present tense of the verb "to be" (am, is, are) is almost always left out. So, instead of saying "This is my address", you simply say "This my address" (Это мой адрес).

Since "адрес" is a masculine word, shouldn't we use the masculine word for "this" (этот)?

Not in this case! When you are introducing or pointing something out with the phrase "This is..." or "That is...", you always use the fixed neuter form это. You would only use the masculine этот if "this" was directly attached to the noun, like in the phrase "this address" (этот адрес).

Why do we use "мой" for "my" here instead of "моя" or "моё"?

In Russian, possessive words like "my" have to match the gender of the noun they belong to. The word адрес ends in a consonant, which makes it a masculine noun. Therefore, you must use the masculine form for "my", which is мой.

Can "адрес" be used for an email address as well as a street address?

Yes, it can. For a physical street address, you just use адрес. For an email address, you will often hear people say электронный адрес (literally "electronic address") or just use the borrowed word имейл (email).