Two thumbs up for FlisKits! Great products from a vendor who will bend over backwards to help you.
As far as that goes, I don't know of ANY vendor that hangs out here that doesn't also pretty much fall into that category. These guys sell these products because they love the hobby.
Be aware that (besides Estes) there is now another major model rocketry supplier, rapidly growing: Quest Aerospace. They have great products and (independent of Estes) also have a motor line for 18mm blackpowder motors.
Before you spot an old collector kit (the term is "OOP" for out-of-production) that makes you go all wet-brained, and before you go on ebay and spend mega-bux to buy one, note that there are tons of plans for old kits posted online for free. Check out
JimZ rocket plans -- https://www.spacemodeling.org/JimZ/index.htm
Ye Olde Rocket Shoppe -- https://www.rocketshoppe.com/
and there are other websites with similar content. If you can't find it there, try asking here on TRF and one of our "historians" may be able to provide it or direct you to a source. And we can help you find the parts and materials for these old plans at places like Balsa Machining Service, Totally Tubular (body tubes), Roachwerks custom balsa spinning, custom decal vendors, and others.
BTW, on JimZ there are also old Model Rocketry magazines that are well worth reading. Tons of good info there that is still useful.
If you have any Hobby Lobby stores near you then you may want to hold off purchasing model rocket kits until next week. Lately they have been running a 40% off coupon about every two weeks, like last week, which means next week they will probably post it on their website again. You can print as many as you like: check https://www.hobbylobby.com/weekly/weekly.cfm
each week on Monday.
Use the NAR website to search for local sections. If there is one within driving distance I would highly recommend getting in touch with them, attending some meetings, and watching for their next launch. Especially if they have any upcoming contest events, stay in touch with them because most of those little groups have a lot of experience behind them.
A big list of rocketry jargon and definitions on EMRR -- https://www.rocketreviews.com/cgi-bin/resources/glossary.cgi
Their list of terminology can help you get up to speed quickly
Lots and lots and lots of good info, advice, experience documented here: https://www.rocketryforum.com/forumdisplay.php?f=41
(THAT oughta keep you busy for a while!)
And come on back here to TRF with more qstns! There are hundreds of more websites full of good info that we can point you to, if you tell us what you need. (Welcome to TRF?
[despite last night's events?])