On-Site Search structure questions

Many times on-site search is an overlooked topic, but the trend of making better on-site search and bringing results that will convert more is growing.
"searchandising"

Anyway, my question is divided in 2 parts.

1 - Do you know of any study or do you have an opinion about giving filtering options to user on the first search? or is it better just to have a search box?

By options on the search I mean there is a search box and a drop down box. An example would be that users can search products for GUYS or GIRLS already on the first search.

So, how do users respond to the layout with filter options on the first search, against doing a simple search, and then refine the results?

2 - Refine options: What do you think works best, having full listing of the options or using drop down menus?

examples:

full list of options would be like:

CATEGORIES
shirt (12)
shorts (35)
shoes (21)

BRANDS
awesome brand (7)
cool brand (12)
crazy brand (8)


Drop down boxes would have all this options in separate boxes, one for categories, another for brands, etc...

What do you think?

I think search is very important, and sharing our experience is good for everybody in this business.

I appreciate your input.

Thanks

drop down boxes isn't really a search facility, more like a directory system if you will.

Filtering options I believe should be given for on-site search when the search returns 0 results (too generic search, no results, etc.) but that's my opinion

Hi dudibob, thanks for your message. I think that offering further options to refine and sort results is very important.
I am trying to figure out whether to show the refine options in drop downs or as a list of options.

Also, if I should have 1 drop down (gender choice) on the first search.

Thanks

I personally prefer to be able to specify exactly what I want on the first search, reducing but not eliminating the need to refine results.

Less experienced users may not be familiar enough to do a targeted search right off and will probably be more likely to need to be able to refine results.

Any reason you can't do both?

I suspect most Internet users become familiar with drop-down boxes fairly quickly. Whether I would use them or actually list every option could depend on how many options there are.

The more precisely you can show someone the options available to them the more likely they'll be able to easily make a decision and buy.