I actually got my most recent futon from craigs list, it is really cool has detachable arms, sits like a couch - not like the old days, and it looks like an mcm couch. i have 2 i keep in my ideabooks to show people as examples:

Bellevue with Retractable Tables Transitional-style Queen-size Inner Spring Futo · More Info

Amazon.com: Home Life Anderson Futon Sofa Bed with Adjustable Arm Rests Brown Li · More Info

now as to where to shop. I know that Amazon has no shipping and good return policies. Walmart will deliver to your door if you do not like i know you can take to store with no fees, and there online store has everything even the expensive stores have, much higher quality than instore is available. same with target and pier 1. lowe's and home depot also have online stores, you need to check theirs, but those return policies seem to be standard. other more unusual stores, i like hay needle, birch lane, and all modern check for complaints have not seen any. now a store i think is great-all kinds of awards, lasting forever, and omg those prices! they make sofas, but if you are getting too expensive they might make a fold out sofa for under $500. sofas start just under $400. not cool, but over 40 sturdy materials, and like i said no complaints. don't forget ikea!