今、あいにくチャットする時間がとれませんが、Unfortunately, I don't have enough time to chat with you, あなたがオンラインのようなので、I notice you are online, ご挨拶のメールをお送りします。I send this mail to say hello, また、よろしくお願いします。Let's chat another time. Thanks you. ------------------------------------------------------------------------------------- よろしくお願いします。Yoroshiku Onegai Shimasu (in Japanese) . This sentence is one of most important in Japan. You can use this in all situations when you want to say hello. The meaning of this is similar to 'Thank you in advance', but Japanese use this phrase many times a day.

Hi. My best shot of translation: あなたがオンラインなので、イーメールを送ろうと思いました。（It's more like I thought of sending you email because you're online). Anata ga onrain nanode iimeeru wo okurou to omoimashita. Anata can be replaced with "Kimi", depending on your closeness with this person (Anata is more formal). If you explicitly want to say "decided" instead of "thought of", you can say "okurou to kimemashita" instead. （送ろうと決めました。） It works for both genders also. Note: I didn't include "I see" explicitly. But it's implied so I think the translation is good enough. I hope this helps :-)