Simply choose the type of band, solo musician or service  that you would like (e.g. Wedding Bands). Then in the “sort by distance, price or ratings” section of the “sort” box (top right of the page) click “price (low to high) or price (high to low)” and hit “sort results“.

E.g.

price

You can also choose to sort results in this way from the home page or advanced search page.