Ok, I will try to keep this short. I retraced a bit of my beginning in 2004.
In 2004, when there was no Pixiv, I discovered my first 3 artist, Akira Hayase, Carnelian and Tinkle. I pretty much searched the heck of them all. Akira Hayase only has her hart on her website, Carnelian, with my 14 years old search skill gave me semi precious gemstone, and Tinkle, well, I did found some stuff and became my first favorite artist, and remained as such, even now.
If there is an artwork in particular I would pick, it's the first one I saw by Tinkle. I remember that it was in a pack of wallpaper. At that time, wallpapers were mostly characters pasted on some background. That one stood out since it was coherent:http://e-shuushuu.net/image/4451/
I didn't use it as a wallpaper but I noticed that I often stopped on this image when browsing that pack, and hopefully, there was the title of the eroge, so I could search. Of course, my nickname is also due to Tinkle :p I still like a lot Merun's design. Long let down hair + ribbon combo, best of both world, pretty dress, thigh highs and cute shoes are icing on the cake :3 It's thanks to them that I like a lot long brown hair with green/brown eyes. Hopefully, Tinkle has been poking at everything I liked in the last 8 years.
Another artist I like a lot is tearfish. It would go as far as sending an e-mail to her. Artstyle is sharp contrast with Tinkle. When one is overkilling with details and sharpness, the other has a certain simplicity, roughness and has a color palette closer to old Tinkle with soft color with hints of vibrancy. She is the reason why I like long white hair + blue eyes. ^^;
Other than these 2, I think that my taste change a lot over time.