I need talk is wong. If you use another verb after need it has to be with to and the infinitive of the verb. So, I need to talk, I need to go, I need to sleep. These are called verb patterns. They are confusing in English because you need to memorise if the verb is followed by to + verb or the gerund. Examples of verbs followed be gerunds are I enjoy swimming or I recommend trying. Unfortunately there aren't any rules for this. You must memorize them.

I usually hear "we need to talk". this is the common way. But "need talk" i guess it just simpler way to direct conversation. -cmiiw

I need to talk to you at large is a right way to say

Exactly but when you say some, it's actually hundreds. You should make two lists. Start with the most common verbs and every time you discover a new verb consult a list online to see if when used with another verb the following verb is to + verb or verb-ing This would be a good start: http://www.perfect-english-grammar.com/support-files/gerund_infinitive_verbs_list.pdf