When I do discover something I think I might want, I look at it online, and bookmark the page, saving it to a folder called Shopping. Most of the time I forget that I had wanted it, but if I remember, I go back to that webpage.
Once I'm serious about making a purchase, or more serious than I was, I make a spreadsheet to compare likely candidates for purchase, including shipping and taxes in order to determine where it's best to buy the item. All of our nearby towns have varying sales tax amounts, so that enters in, as well as delivery charges.
Speaking of my cute little cabin, I know you'd like to know what is inside it.