Reasonable hair extensions in st.Louis?

okk so my hair is like shoulder length and it grows really slow. ive been trying to grow it out but it just wont! its not to thick either and i really want thicker longer hair. soo where can i find a place that will give me nice extensions for a good price. cant be exspensive. but i dont want those cheap clip ons at the same time? somewhere in st.louis or florrissant? No anywhere?