Another person told me:
Learn Photoshop for now, it's the core of a graphics toolbox. Give it at least twelve months of learning, and work big even on small elements (originals of at least 3000px) Get suitable comics fonts, which are a vital element of the comics mix. If you're scanning sketches then of course you need a good A3-size flatbed scanner. If you're then inking and coloring your sketches once they're the screen, you'll want a USB drawing pad and various 'natural media' and 'inking' addon brush packs for Photoshop (there are plenty for free).
But if Photoshop is too daunting/expensive, then be aware that many comics people swear by Manga Studio's brushes for inking scanned pencils.
If you aim to go for animation for animated webcomics later, you'll either want to keep all your character parts and prop parts on different Photoshop layers, for output as animatable elements in SWF format.
Quarkxpress is still a terrible choice to learn, and if you really must go down the print layout route them Adobe InDesign should be your choice.
I'd avoid Illustrator completely (unless you aim to be a work-for-hire pro), as it takes years to learn. If you need to vectorize existing artwork, instead try the cheaper and easier CorelDraw or DrawPlus.
Once you have your backgrounds, character parts, props etc, in SWF, you can animated fairly easily in affordable software like CrazyTalk Animator, which is far easier to animate stories with than Flash.