I want to put lights up on a bridge at my parents place. Instead of running a long line of 110v from their house, can I just set up a 12 volt marine battery charged by a 100 or 200watt panel? The bridge is 90' long so I would need about 180' of string/bistro style led globe lights. Thoughts on if this can work or is there some other approach? Reliable brands of panels, controllers, and converters?

If it's not too expensive, just run the wire. It will be simpler and more reliable.

But if you still want to go the solar route, try to find a complete kit sized for this purpose, otherwise get familiar with the DIY Solar Forum. They will have sizing and product recommendations.

The top brand for 12v systems is probably Victron Energy. They're pricey however.