Well, therein is the reason why evolutionary theory is discounted by many religious apologists: they have this idea that science is only about laboratory observation, and therefore that the theory of evolution is unscientific because massive evolutionary changes in complex species can't be observed in a single lifetime in a lab. The error with that idea is this: evolution takes time, thus we have to corroborate evidence from various scientific fields and not just from laboratory studies of genetics or mutations. That's why we look for evidences in things like geological strata, in the fossil record, in DNA, and in all sorts of other areas.

The more complex an organism, the longer significant, species-changing evolutionary differences take to produce. However, for more simple life-forms like bacteria, evolution has been witnessed and documented numerous times during my lifetime. For instance, mutations have caused antibiotic resistance in various bacteria across the planet. There have been several experiments were isolated batches of bacteria were grown in labs and each were shown to evolve slightly different traits than the others.

Human examples of evolution via natural selection have also been witnessed in my lifetime, though they are only small, because again, significant changes in more complex lifeforms take time. In sub-Saharan Africa, where malaria is a constant threat, many Africans carry the sickle-cell gene. Now, sickle cell, if symptomatic, is life threatening, but if it is not symptomatic then the gene causes no effect other than to heighten the carrier's resistance to malaria. It is no coincidence that this gene mutation has been selected for, nor that it is found most commonly in malaria hot zones. That's a pertinent, current example of an important mutation carried on via natural selection. A carrier of the sickle cell gene mutation with no symptoms is more likely to survive malaria than someone who doesn't have the gene mutation, so it makes sense that they'd live longer and thereby have more chance to procreate in those malaria zones. More chance of procreation equals more likelihood of passing on the gene.

An energy conversion mechanism is a term in physics used to describe the process by which one type of energy turns into another. It gets quite complex, but to simplify: one example of an energy conversion mechanism is the process by which chemical energy becomes heat energy or light energy or sound energy. Ever burned a piece of magnesium? During the oxidation (burning) process it gives off a little heat, a little sound, and lots of blinding white light. Rapid oxidation (fire, burning) is the energy conversion mechanism. If you do decide to try it, wear shades!

And as for some specific pages to look at, try these:

http://www.talkorigins.org/indexcc/CA/CA220.html
http://www.talkorigins.org/indexcc/CA/CA221.html

You can also, if you're on chrome, hit your options bar and go to "find", then type in any words you think might relate to your query, to see if you can find the relevant link on the main page. The main page also lists the queries in categories (palentology, biology etc).

As well as that, I advise you to read up on the basics of mutation > natural selection, and how isolated groups of species diverge. Its actually fairly simple: an organism mutates slightly, and if that mutation benefits the organism in some way, then the organism is "fitter", survives better in its specific environment, thus more likely has a longer or stronger life than its peers, thus has more chance of procreation, and procreation means passing on the mutation. But if a mutation does not benefit an organism, rather instead hinders an organism, then the organism is less fit, survives less well in its environment, thus has a shorter life, less chance of procreation and less chance of passing on the mutation. So, in that regard, nature "selects" mutations.

A great explanation of lots of evolutionary concepts, along with genuine examples, can be found in Prof. Brian Cox's three part TV series "The Wonders of Life". I know, it's a TV show, but it's actually a very visual, factual interesting, fantastically informative TV show full of understandable explanations. Great for beginners.