Wife ok's some new stuff, now what

My wife has given me the green light to invest into some stuff to start a home studio. I really don't know where to start. My budget is not much 200-300. I would like to be able to learn to take better portraits and also start doing some table top macro work.

I already own a Canon 580exII, a Sigma DG530 and an older quantaray flash. Don't know the model number. I also own one light stand. My thought process is to pick up another stand and some light modifiers. I have no idea where to start. Light boxes of what shape? Umbrellas? Etc. should I invest in one of those background stands I see around?

I would really appreciate any help or direction you all may have. Thank you for your time.

if you are shooting inside and don't need to worry about light spill, go with umbrellas.

if you are shooting outside and don't want your light modifiers to do a mary poppins impression, go with small boxes.

If your budget is that small (~ $275), I'd say get another good stand (Manfrotto 5001B - $55), a swivel head umbrella adaptor (Manfrotto 026 - $35). Get a cheap Cowboy Studio umbrella (~ $30) AND one really GOOD brolly box (perhaps a Photek 46" Softliter II - $75) and a Yongnuo YN560III speedlite ($75). That should give you some flexibility in trying some new things.