Living in Texas I of course love the western theme. We had kids of all ages attend so I didn't want it to be too kiddy-like. I wanted even the older kids to enjoy it and feel comfortable. I made pretty much everything even the cake and cupcakes.
Actually my inspiration was my daughter's dress that she wore. It had horseshoes on it. I had purchased it a few months earlier and thought western theme would be a cute idea.
My decorating style is rustic, eclectic on a budget.
The 3 tier cupcake stand I purchased from Save-on-crafts.com. I made the banner, cupcake items and cake bunting from scrapbook paper I purchased from Hobby Lobby. The 2 tin stars I found at Target in the $1 bins. I had some of the table coverings. One of them was an old sheet that my husband has had since he was a kid. The "yee haw" sign I made from unfinished wood piece I found at Michaels that I stained and used twine to do the wording. I also purchase an unfinished stool from Michaels that I stained and used as the cake stand (I used cardboard to place under the cake).
The 3-tier cupcake stand is one of my favorite items and also the banner I made.
Start months in advance and as browsing in stores just look at items to see how you can incorporate them into your theme.