I use Rust-Oleum spray paint.
I think it is a US brand, but it is sold here in Australia. Not sure if it's the same product, or a local license of a US brand name?
I have been using it for years and it seems very durable and quite easy to apply, it is more forgiving of imperfect technique than many cheaper spray-can paints, and doesn't yellow off over time too badly.
Some hints about technique:
It depend on the quality of finish you are after, but if you want a really nice finish, then do two coats of undercoat followed by two or three coats of gloss. I sand off very gently between coats, wet sand using very fine abrasive sponges. If you are sanding between coats, which does help with adhesion and creates a finer finish, then you must let it dry off fully between coats - I mean REALLY dry, several days drying between coats. You can recoat after a few hours, but NOT if you are sanding between coats. Timing between coats is critical to a good job. If you sand off when the paint isn't fully dry, you can tear or lift the paint and ruin the finish.
Follow the can directions carefully regarding time between coats. Usually you can recoat fairly soon after, or not for many hours / a few days. There is a danger period in between - when the surface of the paint appears firm but under the surface, the paint is still soft. If you recoat during this time, the top coat will shrink on the undercoat, causing an ugly crazed texture like crocodile skin. The only answer then is to wait for it to dry, then sand it all off and start again. I've done it...
Using an undercoat gives better adhesion to the base surface, and helps cover very fine scratches imperfections and variations in colour underneath.
Sanding - I prefer wet sanding, use a bucket of warm water (warm just to make it more pleasant to stick your hand in) with a small dash of liquid dishwashing detergent. I like those sanding sponges, they are a layer of abrasive on a firm sponge, they give about the right amount of flex so that they wrap nicely around curved edges without taking paint off the edge. You can also use wet-and-dry paper wrapped around a cork block for the flat sections. Do NOT just hold a sheet of sandpaper in your hand, your finger tips give uneven pressure and you will see ridges in the finishes paint. You need fine or very fine sanding sponges, I'm not sure what grit number but FINE.
Spray cans can give slightly uneven or spattered coverage, and leave a bit of an orange-peel texture. Some of it is in your technique, practise on unimportant surfaces before doing your "real" project. The distance you hold the can makes a big difference, you need to move your hand parallel to the surface so the spray nozzle remains an even distance from the surface you are painting. There is a real "sweet spot" in terms of distance. Too close and you get drips sags and runs; too far and you get a rough, "dusty" finish. I find being a tiny bit too far causes less grief than being too close.
