Haha... are you serious? For a Zigzagoon? I don't remember how hard they are to come across in Diamond/Perl, but in Emerald you can find them under every rock right at the start of the game. Linoone is also easy to find later on, which makes breeding one trivial. Does anybody post normal trades online? I haven't actually bothered with that yet.
Let me put it this way: One time I browsed for a shinx and half of the people offering it were demanding a level 100 palkia in return.

Granted, there are some good trades to be had. It is worth checking out just to do those trades (for example: one time I traded a kadabra for a kadabra; ostensibly the person offered this trade generously so that both people would get alakazam, which I did). However, you will undoubtably have to wade through many unreasonable ones to find the few good people who know how to use the gts right.
I love everything about Metagross. I've even got this little plastic Metagross Pokémon (which I fished out of a random machine by spending around $8) on top of my computer (he's kickin' it with Motoko Kusanagi) and a bigger plastic one near the television which speaks when you press down on him. I've also got a little plastic Zigzagoon somewhere. Nearly all of these things are gifts.
I thought about training one (or a rhyperior since rhyperior looked really cool) but changed my mind in favor of snorlax instead. Snorlax is just such a winner pokemon to me. In hindsight metagross might have been a better tank, but oh well... too late to change that now. :/
I've found a few. It isn't too terrible to come across at least one if you learn to do that grass hunting trick with the Pokéradar (or whatever it is called). I didn't expect I would find one which I liked so much, though, and I was especially surprised to find out he came with a cool nature.
The nature thing is even more unbelievably lucky. Modest and Adamant are quite possibly the two best natures in the game, depending on the pokemon. I actually have a lot of tanks on my team though, so I go for things like careful, impish, etc.
Trapinch kind of looks like chain chomp from the mario games.
