Rather than re-invent the wheel, we are providing links here to various sections of Richard Hefner's excellent ezFolk.com website.

Basic Ukulele Video Course
These video tutorials start with the very basics for people who have never played an instrument of any type and if you follow them through, playing along with the video where appropriate, you will quickly be able to start playing the ukulele.
Find the Basic Ukulele Video Course here.

Strumming Patterns
A complete set of tutorials on strumming (although Richard doesn't use the "DUDUDUDU" nomenclature that is very common elsewhere). Play along with them for practise until you can play them without thinking.
Find ezFolk's Strumming Patterns tutorial here.
Ukulele Go! also provide a set of 32 Strumming Patterns here.

Advanced Strumming Techniques
You can get much more interest into your strumming with finger rolls, flicks and triplets.
Ukulele Go! provide some tutorial videos here.

How To Read Tablature
Tablatures (or "tabs") are a simplified method of writing down music for people who don't read traditional sheet music. For most uke players, if you want to play tunes, as opposed to just strumming, you will need to learn how to read tablatures. Richard Hefner's tutorials on the subject will quickly teach you all you need to know.
Find the Reading Tablatures tutorials here.

Finger Style
Finger Style (or Finger Picking) can add a lot to your ukulele solo playing or used as an accompaniment for a song. It's not always easy to learn but here Richard Hefner provides short video tutorials for 14 standard patterns, starting with the very simplest.
Find the Finger Style tutorials here.

Ukulele Chord Chart
Find the fingering you need for nearly all the chords you are likely to play.
Printable Chord Chart - Ukulele Social's excellent printable chord chart is here.
Interactive Chord Chart - ezFolk's interactive chord chart is here.

Tutorial for Mike Oldfield's Moonlight Shadow
Learn to play fingerstyle with Helmut Bickel's version of Moonlight Shadow. Particularly good if you speak german but worth look at anyway.