Cousin of Mad Libs
If you want to write a thank-you note that makes the recipients feel good and won't have you sitting at your kitchen table picking your brain apart for something new to say in each note, here is a fill-in-the-blank guideline note:

Dear (person's name),

Thanks for the (adjective) (gift description) (date of receipt). I appreciate it because (reason… a good one!) I will (how you will use it). You are (truthful adjective) and (appreciative adjective). (Description of what it means to you.)

Love,
(Your name)

Varying the sentences and form of the note above is highly recommended, and be as creative as you like, as long as you remain sincere. Even if the gift is something that you will drive back to Bath and Body Works immediately to exchange for that new glittery mango body splash, write the thank-you note first and be appreciative. The fact that someone thought about you and gave their time and/or cash for you is noteworthy… even if you don't want or need the actual gift.