When you have a sentence like:

Chaith tú an leabhar.

If you wanted to add "agaim" to it, where would it go?

Is it going to go after the pronoun or subject of the sentence and before the book? Like this?

Chaith tú agam an leabhar.

or

Chaith tú an leabhar agam.

Which would be more correct?

Go raibh maith agaibh.
Sieirál

I'm not sure what you're trying to say. Is it "You threw the book I have" or "You threw the book at me"? In the latter case, it would be "Chaith tú an leabhar liom."

Edit: Regardless, you should find answers to your questions about word order on this page. In general, nominal direct objects precede all pronominal objects and phrases.

(Message edited by Domhnaillín_Breac_na_dTruslóg on August 21, 2008)

The sentence is a bit odd, but

Chaith tú agam an leabhar

in the sense

You threw the book to me (as opposed to at me)

is possible.

So is

Chaith tú an leabhar agam.

They differ in emphasis.

However, I should mention that "Caith chugam an leabhar" would be more usual.

(Message edited by aonghus on August 21, 2008)

Go raibh maith agait, a Dhomhnaillín. Is é sin go cuidiúil! :)
Bhí mé ag rá, "You threw the book at me." Tá fhios agam anois a usaid "le" leis sin.

I hope you don't mind correction
(please let me know if you do)

Is é Tá sé sin go cuidiúil! :

Tá fhios agam anois [gur cheart] "le" a úsáid chuige sin.

Is maith é, a Aonghuis. :) Go raibh maith agat!

Aon Ceist amháin...

Why is "chuige" better to use than "leis", or is "leis" too redundant?

It depends on what you meant.

chuige means (in the context above) "for that purpose"
leis means (again, is the context above) "in conjunction with that"