Learn French: C'est ta raquette, tu me la prêtes souvent pour le match. - It is your racket, you often lend it to me for the match.

In French, when you have two object pronouns before the verb, the 1st or 2nd person pronoun (me, te, nous, vous) always comes before the 3rd person direct object pronoun (le, la, les). So, to say you lend it to me, you must use tu me la prêtes, never tu la me prêtes.

Is me a direct or indirect object in this sentence?

It is an indirect object. The verb is prêter quelque chose à quelqu'un (to lend something to someone). The thing being lent is the direct object (la, replacing ta raquette), and the person receiving it is the indirect object (me, meaning to me).

Since raquette is feminine, why does the sentence start with C'est instead of Elle est?

You must use c'est (or ce sont for plural) when it is followed by a modified noun—that is, a noun with an article or possessive adjective like ta. Even though raquette is feminine, you use c'est because of the determiner ta. You would only use Elle est if it were followed by an adjective alone, like Elle est rouge.

Why is souvent placed after the verb? In English we say often lend.