How Ya'll Doin'?
The Honey Bun Kid
If you're talking about paper nautical charts, then you can get them at most West Marine's. Get the actual NOAA chart -- it's the only one with truely accurate information for navigation purposes. And by the way, you ought to have a paper chart of the waters you're fishing on board anyway. Electronics have a tendency to fail when you least want them to.
If you're looking for paper 'fishing' charts, Hot Spots charts are hard to beat.
If you're talking digital chart chips for your chartplotter/sonar unit... then it will depend on who's machine you're using. Garmin, for the most part, uses their own G-Chips. Good stuff. Navionics makes chips for just about everything else out there, from Lowrance to Raymarine to Furuno. C-Map was probably one of the first on the market and make good stuff too, but they lost their foothold to Navionics.
Navionics also makes the Fish'N chip. It's a more highly detailed chart with less navigational clutter on the screen and focuses more on contours and fishing types of underwater terrain. Navionics also makes their inland digital chips which are the best I've ever seen for lake detail. And you get a LOT of lakes on a single chip.
Where can you get the digital chips? Bass Pro usually has a good supply, West Marine, and marine electronics stores like Bethel, Consumer Marine, etc. Half Hitch Tackle would most likely have them as well.
And Navionics makes digital chart chip app's for iPhone and Droids. Very inexpensive, and very good. Great detail, you just lose some of the functionality that's available on the bigger chips, but the charts are exactly the same. I've really enjoyed mine. Get it at the iTunes store. I think it's around $14 or so.
One final thing -- if you're planning on fishing/navigating in 'other than US coastal waters", you'll really need to take a hard look at the amount of detail each chip provides. Navionics does pretty well in the Bahamas, but has a few 'dark spots' with less than ideal chart detail. Jeppeson has good coverage there, as does Garmin.
We will be giving away a Navionics Gift Certificate for the winner's choice of a Navionics Gold chart chip at the Fish N Fest.