1)The most convenient way I think is download a e-dictionary in your phone. You do not have to buy a new good phone which cost few hundre Yuan.If you have a phone,you could baidu "手机英汉词典下载""手机汉语词典",things like that.It is totally free,good and brief.
2)If you need buy a phone,choose Nokia,BBK,they have dictionary inside.
3)Buy a study machine called (电子词典)dian zi ci dian,it usually costs more than one hundred Yuan.Any e-dictionary got a few dictionaries inside.The e-dictionary is very tiny,you could put it into pocket.
4)Get the book on some book stands.they usually have some breif dictionaries.
5)Buy online(卓越网zhuo yue wang),it is famous for it's discount books and the books are authoritative.You may find some Chinese studing books as well.
Sorry for some inconveniences in China.I feel inconvenient sometimes when need to contact friends abroad.
I used to use a very special software to "jump over the wall".The software could let you go Facebook,Twitter,My space,ect.But it doesn't work right now:(((
So maybe use skype,MSN which are allowed use in China.So that you could see your family via the vedio.
Or you could buy a phone card.It costs from ￥30-￥50,you would have about 60 mintes to 120 minutes.I used 2 cards for a year.so it's cheap.You may have a try.If u do not know where to buy,I could help you.just e-mail me firstname.lastname@example.org.
I saw some hats for Halloween in ShunCheng(顺城) near ZhengYiFang(正义坊,It is a toy store.So I guess it would be more easy to find halloween stuff in toy store.Also you may go have a look in Wal-mart .It probably have Halloween stuff.Good luck!