Stat guidence for a research paper

#1
I am currently in the process of writing up a small research paper, but I am quite rusty on my stats. I was wondering if anyone could recomend either a statistical method or a place where I could find one for my data?

I have gathered the following data:
General age of patient.
Adult (2-7y)
Youth (1-2)
Puppy(<1y)
Geriatric(<7y)

***:
M,F

Type of location where found:
Slum, poor area, middle class, wealthy, market, industrial, butchers shop, open area/wasteland.

Body Condition Score (Hills BCS System):
1-9

Parasites found by faecal floatation
There is a list and they are either positive or negative based on presence of a single egg.

The population size has been counted at 20,000 dogs and I have taken 104 samples.

My goal is to describe the prevailance of each parasite type, which I believe to be easy enough, just the percent of each type found in the total population at any point in time. Is this as simple as I am assuming?

I would also like to calculate if certain parasites are more commonly found in certain age groups or if type of parasite can be correlated to BCS or age or location. This is where it all gets a bit murky. I know I can use a chi2 test to calculate the expected vs. observed, and use the overall prevailance as the expected. Would this be an acurate method to use for this purpose? As you can see I am a complete amature.

I would appreciate any and all help, even just a point to a good book would do!

Thank you
 
#2
But for a population of 20000, you sample size should be 392 at 5% precision level. It is ok if precision level is 10%.

Find out contingency coefficient after calculation of Chi2 value for each independent variable. There are other complicated methods like correspondence analysis or logistic regression if you want to go to that level.

Take other responses also.