Google QRP ham radio and you'll find a few kit manufacturers out there; QRP standing for low power transmitters. A favorite is QRP labs based in Europe, really inexpensive but well-designed kits....however, not recommended for first time kit builders, trust me I've struggled building them and I started my kit building career in the 1960's with Heathkit.
Elecraft sells excellent high end ham radio gear and is very expensive...I currently own the KX3 an amazing QRP transceiver but very $$$. I built a K2 years ago and it took a month and some troubleshooting to get it working.
KE0OG, the ARRL and QST's new technical editor has a website for recommendations on getting into HF radio.
GL/73