IQ2 is right; Knights is a great shop right on US 1. Believe they are closed on Tuesdays. The southern coast of Maine has a great RV park right across from the ocean in York, ME. In May the coast starts coming alive a bit. Wonderful time to visit. Enough folks around to make it interesting without aggravating. Absolutely stop at the Marden's Stores. Almost all fabric just under $5.00 and batiks another $1.00 or so more. I always buy my wide backings there and think they are only $7.99 a yard. Not every Marden's store has a fabric department but most do. Sanford has a large selection but Scarborough's is organized much nicer and may have a slightly larger choice. If you go to Marden's, look for the trays of Whoopie Pies near the cash registers. So good and freeze well.
If you get up to Freeport Me, to go to LLBean, there is a little quilt shop called Cotton Weeds. Small, not a huge selection of fabric but wonderful, unique quilting and needle work patterns. Also, very welcoming and helpful.
Husband and I get to the southern ME coast twice a year. Will be going the week after Mother's day probably. If you need any suggestions for other shopping, restaurants, attractions, just PM me.