Hello! I'm looking for my first tube head, and I have no idea where to start. If you could give me some recommendations that would be great! I'm going to run pedals through it, and play pretty much every genre you could think of. Thanks in advance.
What's your budget? ("Inexpensive" is a relative term.)

What do you want to play?

Where do you live? (Location affects price & availability.)

Are you willing & able to buy used? Online?
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Strap on, tune up, rock out!
Peavey Valveking is pretty cheap overall. Traynor YCS50H, Carvin V3 are also good options. You have many things to consider - if you're going lower volume, under $1000 you could snag Mesa Mini Rectifier, Orange Tiny Terror, Dual Terror, Dark Terror and a few other heads as well.
dannyalcatraz Budget is around the $300 area, I play everything from SRV to Slipknot, and I'm willing to buy used.
Valve King, Jet City,
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
For $300 and under, your mostly going to be looking at Peavey amps. XXX, JSX, and Valveking can all be had for around your budget.
valveking would be my pick, get an overdrive pedal and some new tubes.

a valveking 112 combo is easily had for under $200ish.

Jet City 20 or 22 would be another option as well.

i actually have a VK combo that i just picked up for modding, there is a lot of resources on modding info if that is your thing.