Hey Steve,
You absolutely can make incredible changes ESPECIALLY since you have never lifted before.
If you don't have access to the gym and are serious about getting in shape, I suggest doing the following:
1) Get a stability ball and a set of light dumbbells.
What most people do when they are new to lifting is run to the gym and hire some bs trainer who is clueless or follow a routine out of a magazine. What they should be doing is focusing on themselves. When you first start you should ideally focus on building up your stabilizer muscles. Most newbie injuries occur form improper lifting technique and weak stabilizers on a heavy load. If you are relatively athletic you should advance through this stage relatively quickly. Google basic exercises like dumbbell presses, tricep extensions, rear delt exercises, etc etc. You can do almost every body part in some way or form on a stability ball. Reason for the ball is to help develop your stabilizer muscles since its an uneven surface that must be controlled while also lifting with good form. If you want specific exercises PM me.
2) Start reading around the 'net on how to build an effective diet for your health goals. Bodyrecomposition.com is a pretty good site, Lyle McDonald has good insight and a good beginner program, although I don't agree with any pure newbie like yourself jumping straight into a regular lifting program. Spend time building those stabilizers on a ball, you will thank me later when you don't have shoulder or knee injuries. Also google info on proper posture, which is usually out of whack for newbies.
3) Get a whey protein supplement: protein builds muscle, enuff said, again if you want help with specifics PM me.
Less is more, not only when starting but for all but the advanced client. What are your goals? Have you ever got your bodyfat tested (recently?) Do you do any type of exercise at all currently??
PIMP