I needed major alterations as well and made sure to look for someone who designed and made dresses as well as doing alterations. I figured if they could make a dress from scratch so they could do any alterations.
Welcome to the WeddingWire community, Bethany As the PPs mentioned, reviews are super helpful when looking for an excellent seamstress. Online sites such as Yelp are great for this reason! Where about are you based? Let's see if we can find you some great options!