Conditionals are great, and more than likely you are used to hearing them in everyday speech. If I was a millionaire I would become rich etc etc. If Boro can win a match, I wouldn't be sad every fucking day etc etc.

なら

なら is sorta weird because its used in a similar sense to ば and たら however again the nuance is slight. Unlike the former two, なら expresses a similar sort of nuance to the following;

日本へ行く時に、新しい服を買うつもりだ。
日本へ行った時に、新しい服を買うつもりだ。

What do you mean, you don't know the difference? !!! Well, the first would imply that you intend to buy clothes before you go to Japan, whereas the latter would suggest you will buy new clothes after you go to Japan.

なら is sorta similar, in the sense it implies the required action and preparation before you do something in the conditional sense.

今夏中国に行ったら、「紫禁城」に訪ねたほうがいいです。
If you are going to China this summer, you should visit the "Forbidden City."
今夏中国に行くなら、お金をためたほうがいいです。
If you are going to China this summer, you should save some money (before you go.)

Get it?

Japanese is full of these implied meanings that underly the sentence.

ばいい

Sounds like a Japanese sheep doesn't it? This is a great little thing to use and effective once you know how to use. Sort of like the Rhyno gun on Ratchet and Clank.

If you understand the conditional ば to mean If (something) and the いい is good. Then of course the overall meaning would be "If X is Y, then it is good." Or there abouts. This type of construction tends to be used along with another conditional. For example,

道に迷ったら、交番に行って、けいかんを聞けばいいです。
If you get lost, all you have to do is, go to the police box and speak to the police officer.

My translation would be;

If you get lost, go to the police box, speak to the policeman and all is good. ^o^♪

I suppose for anyone deciding to study at Sheffield my advice would be;
日本語は難しくなったら、先生に話しに行けばいいですね。
If Japanese becomes difficult, all you need to do is go and speak to sensei.

ばよかった

Same as the above, but this expresses the regret at having not performed that action. Hence;

先生に話しに行けばよかったんだなぁ。
I wish I had gone and spoken to sensei. >o<

ばほど・だけ

This is hard to explain, at least for me. Its like, the more you do something, the more something happens. たとえば time;

日本語は勉強すればするほど、やさしくなる。
The more you study Japanese, the easier it becomes.
毎日運動すればするだけ、けんこうになる。
The more you exercise you do everyday, the fitter you will become.

Because many sentences in this type would require a resulting or changing state, になる and にする are often used. The basic construction of the sentence is;

XはVerb conditional+Verb dictionaryほど・だけ

I'm struggling to use this one, even though it is damn effective.