look at a chart. see where the price has been. note support. buy there. right now $019 is nearest support level. very remedial (but better than, "should i buy in the morning or afternoon" ).

but no one can advise someone else "where to buy". since no one is you. knows your financial needs. goals. timeline

if you're convinced ntek is going in the right direction. and going long-term. then anywhere you buy should be fine (assuming market/ntek does what you believe they should)

the 50 ma is now at $.019 (consider placing order about 5% up or down. from support. depending upon price action. L2. desire for shares. volume of shares intended to target. acquire)
http://stockcharts.com/h-sc/ui

from $.019/$.0188 might be a good place (i have $.0188 order in currently)

but again. your money. your call. it's your cash you are risking. my advice is simply better than "morning or afternoon" (in my opinion. of course)