Unless you already have painting supplies that you love, you'll be able to shop tools like rollers and tape directly on these websites.
Backdrop
Backdrop sells one main Essentials Kit, which has 11 pieces, costs $45, and includes tape, 2" paint brush, 9" roller frame, two 9" roller covers, 4" roller cover, 4" roller handle, tray, and three tray liners.
You can also get these supplies, as well as a few others (putty knife, spackle + sandpaper kit, painter's shirt), a la carte.
Clare
Clare sells four different pre-set kits, ranging from $15 to $50. Its largest kit has eight pieces, costs $50, and includes a plastic drop cloth, tape, 2" paint brush, 9" roller frame, 9" roller cover, 9" metal tray, 9" tray liner, and 2-4' extension pole.
You can also get these supplies, as well as a few others (mini roller frame and cover), a la carte.