"Any strategies for finding a Shiny?"
Depends how you want to encounter one:
1) Breed - Simply keep obtaining and hatching eggs until you find the shiny version. This method is best used for rare Pokemon, like Ralts, Bagon or Feebas.
2) Soft Reset - for Event Pokemon only. If you want a Purple Kyogre or Black Rayquaza, use this method. The quickest method out of all of them, but still slow and painful. If it takes 30 seconds to attempt getting a shiny, you will theoretically spend 68 hours doing so.
3) Wild - simply run about in the grass where the Pokemon you want is usually. Eventually, you will encounter the shiny.
"So... Finding a Shiny in Ruby, Sapphire, Emerald, FireRed, LeafGreen, Silver, Gold or Crystal is exactly the same as how I can get them in Diamond/Pearl?"
Yes. There is no difference in the method of obtaining them. In fact, apart from the fact that Shiny Pokemon in the GSC generation had slightly higher stats, nothing has changed.