i'd suggest finding whatever tracks are local to you and contact that promoter or club. Wait until the beginning of next season and attend some of their events. See what classes (kart/engine/weight) they run and what vendors support their events. Try to get into and entry level class that's well attended. Used equipment starting out is usually a good idea.
As flattop stated, margay is a relatively local kart manufacturer and offers a turn key package with a briggs lo206 engine ready to go for about $4500.
Check out their website.
But look around at your local clubs first!
There is no rush. You want to buy the right equipment the first time!!! Keep asking questions!
Welcome, have fun with your search,
clark gaynor sr.