Discus Launch Gliders (DLG) are an exciting and convenient way to get into the sport. You don't need a special site to fly your DLG -- a school yard or small park will do with a small DLG glider such as the E-flite UMX Whipit. As you advance in skill you can get incredible performance from high-end DLG gliders.
Here are some companies that offer DLGs and other gliders:
Armsoar ; https://www.armsoar.com/collections/gliders-1
Soaring USA : https://www.soaringusa.com/dlg-hlg-f3k/
HyperFlight UK ; HyperFlight DLGs
DLGs are launched by hand as demonstrated these videos: