I have made lots of the things that you are looking for but it takes several days of work and searching for clipart to make all of the printables for a party and I have a lot on my plate right now.
Here are two images that you can use to make everything you want. If you like them, please don't quote them as it takes up linking space in my photobucket that I can't delete. Also make sure you save them (if you want to use them) as I clean out my photobucket weekly:
Cupcakes: Resize the image to 2 inches and purchase a scollop circle punch that is 2.5 inches and a coordinating cardstock like red bandana, a solid red, or even a fun cowprint. Then cut the scallop circles out of the cardstock paper and voila, you have your cupcake toppers.
Water Bottles: Purchase a fun scrapbook paper either regular weight or cardstock and cut strips to go around your water bottle. The easiest way to firgure out the size of strips is to take off the water bottle label (from the water bottles you intend to recover) and measure it. Make sure that you leave extra space to overlap the ends. Then resize one of the circles, place it over the center of the strip and cover both with clear contact paper. That way if it gets wet, the image won't smear. Then use double sided tape to attach to the water bottle.
Napkin Rings: Cut strips of the fun color scrapbook paper to use as napkin rings and get a solid color (like red) napkin to wrap the strips around. You can also resize one of the circle images to put on top of the napkin ring.
Bag Topper: Also use the fun scrapbook paper (you will need a heavier weight cardstock for a bag topper) and cut out a square the width of the bag you want to top, then fold it half and put over the bag. A fun bandana or cowprint would be super cute for this as well!
That should get you started and if you find the right paper at Michael's, Hobby Lobby or a craft/scrapbook store where you live...everything will be super cute!
Hope that helps!
