You can download a free trial of Lightroom etc from
Download a free trial or buy Adobe products | Adobe downloads
I have Lightroom and the latest Photoshop, you can "rent" them for £8 ish a month and they update themselves over the web, well worth it.
To get the best from Lightroom you need to be shooting in RAW. It allows you to edit photos and adjust the levels to bring the best out of your images.