New nominal codes

Hi,

Default posting code is "other creditors" for posting Accruals, director current accounts etc. However I like to keep them seperate at the level of TB or nominal, I know that for statutory accounts purpose these should be merged. 

Is there any way that I can create some additional codes in debtors and creditors etc in the master file so that every time I create a file for a specific client it will have these nominal codes rather than re creating for every signle client and then amending teh formulas. 

Also at the level of master file can I add headers or footers so that every file copies them automatically. 

Regards

Asim