Buying seeds and sowing

Ok, apologies in advance if this is a daft question...... I have found some seeds I would like to have a go at growing, my question is this, would it be ok to buy the seeds now and save them until spring ( when I think, they should be sown ? or would it be ok to sow now ?  I did say that I know nothing about gardening in general, let alone growing cacti ).

After you finish shaking your head at, what is probably an easy/obvious answer, please help   

Thankyou  

Yes 6 moths or so should be fine. Germination rates tend to decrease between 1-2 years for most cacti. Yes there are some exceptions and some that don't become viable until after a year but as a general guide you should be fine.

You can sow them now but you just need to use an appropriate technique and keep the temperature and humidity constant.

Thanks Hn, I'm looking at getting some Mammillaria seeds. I will read up about how to go about it and decide from there.