okay so i have a 2000 ls v8 3.9 and its been sitting for almost a year but i have started it throughout that time and drive it sometimes. so now its been sitting for about a month and i ran it yesterday for about 25 minutes.
today the engine doesnt start!!!

just a single click sound.

i guess that comes from the starting relay?
its very cold here in CT - about 10 - 20 degrees this weekend. i thought it might be the battery so i went to walmart and bought a new one but the same one click happens and car doesn t start nor turn over at all, just "click"

so can someone help me out, please????