Correspondance

I'm trying to write a letter in Khmer. How would you say the 'Dear', as in 'Dear someone...', at the beginning of the letter ?

Later : I've found something in a book. It seems one uses a variation of :
ជូនចំពោះ+ someone +ជាទីនឹករលឹក
which means 'To + someone + whom I'm often thinking about'.
That will do.