Let's start with the guitar because this has a direct effect on you progress. If you get a quality guitar it can be set up to play very easily and this will help you play through those complicated passages or intense chord changes with ease. There are many manufacturers that make great electric guitars such as Gibson, Peavey, Fender, ESP, Ibanez, Washburn, and Jackson to name a few. But depending on your needs, there are some variables to be considered.
If you are more into blues or traditional rock music, a more classic-style guitar such as a Gibson Les Paul or SG or a Fender Stratocaster or Telecaster would probably suit you best. There are also hollowbody electric guitars such as the Gibson ES335 that get a warm, full tone and are used by many blues, rock, and jazz guitarists.
Here are some other things that can shape the sound of your guitar:
Type of wood: Hard and dense woods will create a thin tone with lots of high end while soft, wide-grained woods will give you a warm, full-toned sound. Some of the most common woods used are ash, alder, walnut, mahogany, koa, and maple.
Pickups: There are two main types of pickups to choose from—active and passive. Active pickups, used by many heavy-metal guitarists, have a battery-powered circuit and high-gain output. The most popular brand of active pickups is EMG. Passive pickups are known for their warm, full tone and there are many manufacturers that produce great passive pickups.
I recommend you go to a music store and play several different guitars to see which one feels best under your fingers. Guitar necks can be wide, thin, fat, round, oval, or any combination of those characteristics. It's like buying a new pair of shoes—you want them to look great, but they have to feel great first.
When you get to the intermediate level as a player you have to start thinking about playing with other musicians and your amp has to have enough power to be heard along with other instruments such as the drums (unfortunately drums don't have volume knobs!)
Again, as with guitars, there are many companies that offer great-sounding amps, but there are a few that may suit your music style best.
There are two main types of amplifiers—tube and solid state. The main difference is tube amps use a system of overdriving tubes to create a thick, full sound while solid state amps use electronic circuitry that creates a typically crisper sound. I would recommend at least a 30-watt tube amp or 100-watt solid state amp for playing with other instruments.
Other features in amps are:
Multiple Channels: This allows you to set specific tones for rhythm, lead, and clean sounds.
Reverb: It adds a room ambience to your sound
Direct Line Out: This allows you to record directly into a mixing console
Effects Loop: This adds your effects into your sound before it goes into the preamp stage
These are what I call my "toys," those addictive little boxes that keep my bank account very low! With effect boxes you can alter your sound in many ways. Here's a list and brief description of some of the most popular effect types. The rest is up to you (and your bank account).
Distortion: This pedal gives you that fuzzy rock or metal sound and is usually applied to a clean guitar sound.
Overdrive: Produces a fuzzy rock sound similar to distortion, but overdrive pedals often provide just a little kick and are often used with amps that have a little distortion but need a boost.
Phase: This gives you an even, swooshing sound by varying the sound wave to achieve the effect.
Flange: Creates a sound the same way as the phase pedal, but flangers give you an uneven wave-form.
Digital or analog delay: These repeat whatever you play at varied speeds and lengths. I often use this for my lead guitar sound.
Wah wah: A foot-controlled pedal that creates a (I know you would have never guessed) wah wah sound. It can make the guitar sound like it is talking!
Sampler: This pedal records your playing then plays those sounds while you play something else over it. It's almost like you are being cloned!
Tuner: Everyone needs this pedal. Step on it to tune your guitar using the meter, step on it again and you are ready to rock in-tune; a beautiful thing!