Hi
I can't really recommend anything, since all of my knowledge comes from working online. All I can suggest is that you familiarise (and I do mean "really" familiarise) yourself with all the various forms of information available. Also, don't be afraid to ask folks for translations of pages in, for example, French.
You will find, as I have, that the same type of information (e.g. French Canadian Catholic church records) is presented in many different forms, some in latin, some in french, some in english, some in combinations.
Another useful point is that the spelling of names often depends on the primary language of the person completing the form, hence I have found a county death record for Mary King, when the person I was (initially) searching for was actually Marie
Roi...
Sometimes you just get lucky - e.g. when you look at a search result, check out the pages either side for possible additional information. If you get stumped (and this is where the catholic church records are useful) try searching the god-parents names (as many will have been close relatives).
In the end, you may well develop a feel for the style of the records, at various periods in time, and will start to know where you are more likely to find a missing piece of information.
Above all, when you get stuck, ask.
good
Luck.