Does it have the sticky stuff already applied

Yes, the Weatherproof Polyester Laser (LP) material is a self-adhesive label product. This features a strong, permanent acrylic-based adhesive that works well on a variety of dry and wet applications.

How do these labels fit on a 16.9 oz water bottle from Walmart (Great Value)?

While we haven't tested this brand of water bottle, the OL435 fits most 16 oz bottles. To ensure you select the right size for your bottles, we recommend printing our ruler at the link below to confirm. https://www.onlinelabels.com/docs/rulers/Printable-Ruler.pdf