If you really had a job, you couldn't get enough time off to go to Japan. Just keep studying Japanese and maybe we'll go together some day.

もし、ゆっくり休みがとれたら、--アメリカにいって、いろいろな人に会いたいです。でも、今もし休みかとれても、子供が大きくならないと無理かな？
if I took long vacation I would visit America and meet many people. BUT-- If I could take it, it would be hard to visit your country, because my kids are still little.
WO!!! English is difficult!!

My version follows, FYR only.
もし私に仕事があったら，お金が（いくらか）手に入るだろうな．
（すこしでも）お金が手に入ったら私は日本に行くだろうな．
日本に行ったら温泉に行って，お酒を沢山飲んで，おすしを沢山食べるだろうな．
（そうすると）私はとても幸せだろうな．
でも，幸せすぎればアメリカに帰りたくなくなるだろうな．
もし帰らなければ（多分，ですが）主人が寂しがるだろうな．
ということで，私に仕事がないということはいいことなんだ．

これ↑って，一種のオノロケですよね．
ゴチソウサマでした．

Should have put the following para at the top of my last posting:
私がプログラマーだった頃，「もし何々だったらこれこれ，さもなければこれこれ」，という条件文の作り方を知っていることが大切（たいせつ）or重要（じゅうよう）でした．この前の月曜日に（日本語学級で）「もし何々なら」という言い方を習いました．大変面白かったですが，ちょっと難（むつか）しくもありました，本当にそれ（そのいいまわし）を習得（しゅうとく）するまでには，たくさん練習（れんしゅう）する必要がありそうです．

Wow. I can understand what you're both saying...well, for the most part.

One thing I find confusing is もし. My textbook says, "The conditional clause is often preceded by もしも or, more commonly, もし both of which emphasize the suppositional nature of the clause."

Even though that sentence is written in English, I'm not sure what it means. (An example would have been nice.) Is using もし sort of like saying "If only" in English?

I don't think "emphasise" in your textbook is a good word there.
While "if", by itself, converts the sentence that follows into a suppositional or conditional one, �もしも�　or �もし� signals or tells you the beginning of a suppositional or conditional sentence/phrase and needs or anticipates such a closing component to complete the supposition/condition as �ならば�．
In another word, unlike "if", �もし or もしも� alone does not consummate a supposition/condition.

( let's focus on �ならば� version of the closing for now and study other variations of a closing element that there are as they come up.)
Let's look at our examples:
(This time I'll try to be as close to English texts as possible)
If I had a job もしorもしも（私が仕事をもっていた）ならば
If I had any money　もしorもしも（私が金をもっていた）ならば
If I went to Japan　もしorもしも（私が日本に行った）ならば
If I were too happy もしorもしも（私が幸せすぎた）ならば
If I didn't come back もしorもしも（私が帰ってこなかった）ならば
So,I think we can safely say that "if" corresponds to �もしorもしも・・・・・・・ならば�.
Need a few more examples?
If it were hot もし（も）暑（あつ）かったならば
If the price were lower もし（も）値段（ねだん）がもっと安（やす）かったならば
If I were you もし（も）私が貴女（あなた）であったならば
If it is fine tomorrow もし（も）あす天気がいいならば
If my take-home pay were double what it is now
もし私の手取（てど）り給料（きゅうりょう）がいまの2倍（にばい）であるならば

"If only" can, in many instances, be expressed by inserting ”さえ” somewhere in ”もし/もしも・・・ならば” expression．
Examples:
If only I had a million dollars
もし（も）百万ドルを持（も）ってさえいたならば
Compare this with:
If I had a million dollars
もし（も）百万ドルをもっていたならば

If only I were a genius
もし私が天才でさえあったならば
Compare this with:
If I were a genius
もし私が天才であったならば

If only I had a Ferrari
もし私がフェラリさえ持っていたならば
Compare this with:
If I had a Ferrari
もし（も）フェラリを持っていたならば
(I could have won the race!)