where can i find a wire stripper for underground wiring? saw it on a show but cant find it anywhere? any hints??????? thanx

Greetings, On adding some outlets in a basement, Ive decided to pull another circuit -from new breaker in breaker box, through garage, to basement. Will be using 1/2" flex couple of feet from box to garage wall, 1/2"emt to metal box in basement, then Romex inside basement along side other Romex to GFCI, then 2 other outlets. Home Depot person said I could not run Romex inside conduit (I will use 12 thhn solid for conduit run) as the Romex is conduit and you can't install conduit in conduit. Any comments on this? Seems to me I've seen pictures in electrical "how to" books showing Romex in conduit. Any other comments are appreciated. Thank You, Randy