As a handmade and thrifty loli I can definitely recommend this way of building up your wardrobe
smile I haven't made very many lolita clothes so far, but I used the commercial pattern New Look 6599 to make a very cute strawberry-print blouse. I modified the pattern a little to have a totally button-up neckline with a button-up collar. I put less lace on than the pattern showed and left off all other details apart from the lovely ribbon corseting at the back.
http://www.simplicity.com/dv1_v4.cfm?design=6599I chose to make style C with style D's sleeves.
http://www.simplicity.com/designFrame.cfm?dvPage=designFrontBack.cfm&design=6599The great thing about me making it myself was that I bought cute ladybird buttons for it, and I made the front darts smaller to accomodate my little pot belly
biggrin This pattern is fairly involved, so I only recommend it if you have sewn other clothes before and are happy with making darts and attaching sleeves. Otherwise, maybe try a skirt for a simpler project.
I made circle skirts so far, but I think that gathered skirts made from a rectangle of fabric might yield better results.