Usually this would be accomplished with the help of guildmates. People are more willing to help out guildmates because when your guildmates are stronger, your guild is stronger. Anyway, why don't you check out
<Stream Team> and
<Castle>? We raid together. We'd be glad to have you. Both guilds have a significant percentage of non-prime-time players.
Unless you speak French, then join <Les Irreductibles>.