Go through your results for flights to El Paso in USA with Netflights. The most popular airlines for this route are British Airways, Virgin Atlantic & United Airlines, with British Airways claiming the top spot. Although Virgin Atlantic usually has the best prices, it's best to double check what's available for your travel dates.
If these flights are too expensive, try searching for a different time of year. It's likely that prices for both flights and accommodation in El Paso will be higher during September. Meanwhile, July is nearly always the cheapest time to fly. So if your dates are flexible, consider looking at different times of year.
El Paso receives 28 direct and indirect flights every week, but the cheapest airline is normally Virgin Atlantic. So, if the flights to El Paso don't work for you, you could always try searching for flights to other airports in USA.
For even more options, check what other airports you could fly to El Paso from. You might be able to make a saving by going from a different airport or city.